Project Summary/Abstract This K07 proposal details a comprehensive career development program that will provide the applicant (Carissa Low, PhD) with the support, knowledge, and skills needed to become an independent behavioral scientist in cancer research. Building on her background in clinical psychology and psychoneuroimmunology, Dr. Low?s goals are to develop scalable behavioral interventions for patients undergoing potentially curative cancer surgery and to examine the effects of these behavioral interventions on clinical outcomes and biobehavioral mechanisms. To achieve these goals, the candidate and her mentors have designed a comprehensive program of training activities and mentored research in the following areas: 1) conceptual and methodological training in physical activity and sedentary behavior research; 2) technology- based behavioral assessment and intervention; and 3) clinical issues in surgical oncology. The proposed mentored research will use knowledge and skills acquired via the training plan to refine and test a novel technology-supported intervention to reduce sedentary behavior before and after cancer surgery. Capitalizing on emerging mobile technology, the intervention will integrate real-time wearable sensor and patient-reported data from the preoperative waiting period to 30 days post-hospital discharge to detect prolonged sedentary bouts and displace low- energy sedentary behavior with brief walking breaks. The frequency and duration of walking breaks will be personalized based on participants? fluctuating symptom burden. After an initial study to field test and refine the algorithm and intervention, Dr. Low will conduct a randomized controlled feasibility trial of the technology-supported sedentary behavior intervention. Measures of feasibility will include retention, adherence, and patient-reported acceptability, and primary outcomes include objective activity levels, patient-reported depressive and physical symptoms and quality of life, circulating inflammatory biomarkers, and 30-day postoperative outcomes. The proposed research will provide pilot data for a R01 application to fund a fully powered randomized trial of the technology-supported sedentary behavior intervention. Although this initial study focuses on patients undergoing curative surgery for metastatic colorectal or peritoneal cancer, the proposed approach is likely to have broad applicability across other cancer patient populations facing similar challenges. The proposed multidisciplinary training and mentored research complement Dr. Low?s previous research and will facilitate her transition to an independent researcher and leader in mobile health and biobehavioral oncology research.